Question 1153179
Ho: mu is greater than or equal to 16.2
Ha: mu is less than 16.2
alpha is 0.05 P{reject Ho|Ho true}
one tail test because suspect difference will only be less.
test stat is a t df=24 0.95
critical value is t<-1.711
t=(14.8-16.2)/2.4/sqrt(25)
t=-1.4*5/2.4=-2.92
reject Ho because t is less than the critical value of -1.711. There is evidence to support the claim that the mean is less than 16.2 in smokers.

Can make a Type I error, of rejecting the Ho given that it might be true, although the probability is small (0.0038)